Progress M- 4

NSSDCA/COSPAR ID: 1990-072A

Description

An improved version of cargo freighters used to supply the Mir space station, the Progress M series had greater cargo capacity, a modernized approach/docking system and carried 2 solar panels to generate electrical power. Progress M can fly for 30 days independently and 108 days docked with Mir. Spare propellent in Progress M's tanks can be transferred to Mir before it is consigned to burn up in reentry. In the past, extra fuel was abandoned with the craft. Future Progress vehicles will carry a recoverable reentry capsule for the speedy return of up to 150 kg of material from Mir to earth.